The invention relates to a liquid filled container referred to as a “water globe” or “snow globe”; and more particularly, to an improved sealing plug for such a container.
This invention is a further improvement on an earlier invention by the same inventor entitled Sealing Plug for a Water Globe, Ser. No. 09/795,994, (issued on Apr. 1, 2003 as U.S. Pat. No. 6,540,099) and is incorporated herein by reference.
A water globe typically comprises a transparent spherical globe that is filled with water and containing a small ornamental figurine. By means of the water and the convex lens effect of the sphere, the small ornament within the water globe generates an enlarged view that appears to fill the globe. The liquid usually further includes tiny suspensible particles, so that when the globe is shaken, the particles are dynamically suspended in the liquid and momentarily provide the illusion of a snowy scene around the ornament. Some snow globes include motors or pumps to continuously move the ornament or agitate the fluid to provide an interesting display.
A conventional seal for a water globe consists of a hollow cylindrical rubber plug having an enclosed flat upper surface. It is well known that water globes may undergo extreme temperature changes, particularly during shipping, that results in expansion and contraction of the water within the container, and sometimes resulted in loss of water and the formation of air bubbles within the globe. The present inventor has minimized this problem with his earlier invention comprising a plug having an expandable diaphragm for compensating for changes in volume within the globe.
FIGS. 1-2 illustrate a water globe utilizing the inventor's prior art sealing plug, and shows a transparent crystalline spherical globe 10 that has a large circular opening 12 at the bottom thereof with an extended cylindrical skirt 14. The globe is filled with a liquid, primarily water sometimes including an alcohol anti-freeze mixture, and is sealed at the skirt with a hollow cylindrical rubber plug 16.
The plug has a cylindrical wall 18 having about three or four extended supports 20, evenly spaced at the upper end of the wall that supports a plastic disc 21 that further supports a small decorative ornament 22 within the globe. The plug includes a flexible diaphragm 24 connected to the peripheral wall by a recessed annular channel 26. FIG. 1 illustrates the plug in the “as molded” configuration with the internal liquid (and internal pressure) acting on the upper surface of the plug. This configuration indicates the minimum internal volume and pressure within the globe.
FIG. 2 illustrates the flexibility and range of the diaphragm of the plug, to expand corresponding to variations in the internal volume of the water within the globe, to normalize any internal pressure that may be created by extreme environmental conditions. Any internal positive pressure on the diaphragm 24 causes the diaphragm to initially flex and bulge downwardly to normalize the volume of the globe. Under more extreme internal pressure, the diaphragm can pivot about the base of the annular channel 26 and invert downwardly (as shown) to significantly increase the internal capacity corresponding to the volume of the liquid within the globe, while the object 22 is securely supported within the globe on the plastic disc 21 attached to the extended supports 20 on the peripheral wall.
The plug with the flexible diaphragm is a significant improvement over the earlier prior art; however, the supports on the peripheral wall are relatively small and sometimes difficult to align for bonding to the plastic disc. Also, the disc, on the supports, extends to the outer diameter of the peripheral wall of the plug (and at the inner diameter of the skirt of the globe) and the plug is sometimes difficult to insert within the skirt of the globe. Also, the supports on the peripheral wall usually engage the skirt of the globe and tend to flex upon installation, and the bond at the plastic disc may be weakened and may subsequently become separated.
In view of the foregoing, it is an object of the present invention to provide an expandable robust sealing plug for a water globe, having supports for an object within the globe that are inboard and independent of the peripheral sealing wall, that is easily and reliably installed within a water globe.
It is another object to provide an expandable robust sealing plug for a water globe, having supports providing a cumulative large inboard area that do not require a plastic disc to support an object within the globe.